Answer

Maximum stress in the system is: $\sigma = -187.1 \MPa$.

Point B moves $0.054 \mm$ to the right.

Solution

Our approach

The system is statically indeterminate since there are two unknown reaction forces but only one horizontal equilibrium equation. In other words, it isn’t enough to only consider equilibrium, instead, we must combine equilibrium with compatibility equations and material relations. Only then can stresses and deformations be determined.

Equilibrium

Consider a free-body diagram around point B and establish equilibrium to determine a relationship between the normal forces in the bars:

$$
\leftarrow: \quad N_1 – N_2 = 0 \Rightarrow N_1 = N_2
$$

As we see, the normal force is the same in both bars.

Compatibilty

The total deformation $n$ of the system is zero and is is calculated as the sum of deformation of each bar: